Process of manufacturing paper



UNITED STATES PATENT EEicE.

NOA H BRYANT, OF OTSEGO, MICHIGAN.

PROCESS OF MANUFACTURING PAPER.

SPECIFICATION forming part of Letters Patent No. 593,011, dated November 2, 1897.

Application filed September 5 1896. Serial No. 605,037. (No specimens.)

To aZZ whom it may concern.-

Be itknown that I, NOAH BRYANT, a citizen of the United States, residing at the village of Otsego, in the county of Allegan and State of Michigan, have invented a certain new and useful Process of Manufacturing Paper, of which the following is a specification.

My invention relates to improvements in the process of manufacturing paper, and more particularly to improvements in the process of manufacturing paper from waste paper. In the manufacture of paper from this material heretofore quantities of metallic particles, pieces of parchment, rubber, and other foreign substances find their way into the finished sheet, causing rust-spots and a great many imperfections in the said finished sheet of paper, and there is also much needless wear and tear on the machineryin grinding the bits of metal referred to which pass into the finished sheet. These foreign substances referred to are in the raw material as tacks or staples for holding the sheets together and also mixed with the sameas Waste.

The objects of my invention are therefore to provide an improved and effective method. to remove all of this foreign matter during manufacture and before the pulp is ground, and to save wear and tear on the grinding machinery, and to produce a superior article of manufacture as a consequence. I accomplish these objects by the method, process, and means described in the following specification.

In the manufacture of paper from waste paper I first cause the raw material to be carefully and thoroughly sorted by hand and all foreign matter removed in that Way that it is possible and practical to detect, though great care in sorting is not absolutely essential. The paper is then thoroughly dusted, then submitted to a boiling in alkali mixture to loosen all ink, oils, and other material. The material is then passed through awasher, where it is thoroughly washed and soaked and reduced to a coarse pulp, avoiding any grinding action. This coarse pulp is then passed through a pulp-screen having elongated slits, comparatively coarse, to allow a free passage of the pulp in its coarse condition, but of such a dimension as to engage the heads of pins and articles of that character. When this coarse pulp is drawn through this screen, there will be found in the screen a great quantity of foreign matter, consisting principally of numerous bookbinder-staples, tacks, pins, pieces of rubber, pieces of parchmentized paper, and parchment, all entangled with a sufficient quantity of the coarse pulp to retain them securely upon the screen.

The screen used by me is a screen which has suction devices below the screen-plate,

which draws the pulp through with great force.

The pulp could be forced through by other means. The pulp is so coarse that some force is required other than its weight. The pulp which has been screened is then passed to the heaters and to the jordan, and then to the paper-making machine, where the pulp is passed through a fine screen before going to the machine, which has the effect of completely screening out all foreign material left, leaving the sheet of paper as it comes from the machine free from blemishes and imperfections of any character due to the presence of foreign material in the pulp.

The screening of the pulp as it passes into the paper-machine is not my invention, but it is the means heretofore depended upon to remove all foreign matter from the pulp, which it did not successfully accomplish, owing to the fact that the foreign material had been disintegrated and ground until there were particles so fine that they passed readily through the screen, causing an injury to the paper and the blemishes to which I have referred. My invention consists, mainly, in the discovery of the fact that all this foreign substance can be practically removed by screening the coarse pulp before it passes to the heater and before it is ground. By screening the pulp at this time the coarse pulp entangles itself around the objects, as I have indicated, and the clear pulp passes on to the beaters and jordan.

It will be seen from this that my improved method and process saves the Wear and tear on the jordan and beating-engine occasioned by grinding these foreign substances, which consist principally of small pieces of metal, and also removes the foreign substance before it has been ground so fine that it will pass through a screen and before the pulp has been disintegrated to such an extent that it will not tangle the same to retain them with certainty upon the screen. I am aware that the use of screens in paper-making is not new, and I do not Wish to be understood as claiming the screen, broadly, as my invention.

My invention consists of the process and in the discovery that the screening is effectual in the early stages of the manufacture before the pulp has been disintegrated, so that it will not serve as an entangling means for engaging the foreign substances and in that way assisting in the removal. Further, my process removes these foreign substances from the pulp before they have become so far disintegrated and pulverized that they will pass any screen that is intended to exclude them.

Having thus described my invention, what I claim as new, and desire to secure by Let ters Patent, is-

1. In the manufacture of paper from waste paper, the process consisting of first Washing and soaking the paper to reduce it to a coarse pulp, next screening the same by forcin g it through a suitable pulp-screen of coarse mesh, then grinding and beating the same and then passing it to the paper-machine where the pulp is again screened and made intopaper as specified.

2. In the manufacture of paper from waste paper, the process consisting in washing and soaking the paper until it is reduced to a NOAH BRYANT. [L.

Witnesses:

N. WV. MfLLs, H. H. MARTINDALE. 

